The present invention relates to a scroll compressor comprising a sealed container in which a fixed scroll including a spiral lap, a swingable scroll including a spiral lap and an electromotive element are provided, and configured to discharge, to a discharge pressure space in the sealed container, a refrigerant compressed by gradually reducing, from the outside to the inside, a plurality of compression spaces formed by engaging both the laps with each other.
Heretofore, a usual scroll compressor has been provided with a compression element provided in a sealed container and an electromotive element which drives this scroll compression element. Moreover, the scroll compressor comprises a fixed scroll including a spiral lap vertically provided on the surface of a panel board, and a swingable scroll including a spiral lap vertically provided on the surface of a panel board and swiveled by a rotary shaft of the electromotive element with respect to this fixed scroll. Moreover, the compressor discharges, to a discharge pressure space in the sealed container, a high-temperature high-pressure refrigerant gas compressed by gradually reducing, from the outside to the inside, a plurality of compression spaces formed by engaging both the laps with each other (e.g., see Japanese Patent Application Laid-Open No. 2008-138644 (Patent Document 1)).
On the other hand, an investigation has been performed to lower the noise level of a rotary compressor, thereby decreasing noises having a high sound pressure level and a harsh frequency among pressure pulsation components of the rotary compressor as a noise source. If these frequency components can be decreased by a certain method, another high-frequency noise is left, but the noises can be reduced to such a level as to be less anxious. To solve the problem, a plurality of spaces (side branches) connected to compression chambers in a cylinder are provided in one of upper and lower ends of the cylinder or one of cylinder contact surfaces of upper and lower bearings which hermetically close the upper and lower ends of the cylinder, and pressure pulsation components which especially noticeably influence the noises are damped to lower the noise level in the spaces (e.g., see Japanese Patent Application Laid-Open No. 10-37884 (Patent Document 2)).
Although the noise level is lowered in the scroll compressor in the same manner as in the rotary compressor, the noises are decreased mainly by the improvement of a muffler chamber. Therefore, a problem remains that harsh noises are left without any noticeable improvement.